This invention relates generally as indicated to a limited angle torque motor with wide rotation poles. More particularly, this invention relates to certain improvements in limited angle torque motors of the type shown in U.S. Pat. No. 4,510,403, assigned to the same assignee as the present application. Such motors are especially suited for use in certain types of high pressure fluid proportional servo control systems including, but not limited to, aircraft controls for driving proportional control valves of relatively short stroke. The fluid pressure may, for example, be on the order of 1,000 psi or more.
Heretofore, one of the limitations of previous limited angle torque motors of this type has been the inability of the motors to achieve a relatively large working angle, in the range of .+-.40.degree. of rotation of the motor output shaft, without compromising the reluctance torque spring rate of the motor through null.
In such a motor, it would also be desirable to increase such useful working angle without increase in current. Furthermore, it would be desirable to achieve a more linear rotation angle versus current for more uniform control of valve flow when installed on a hydraulic flow control valve.